1 /* 2 * Copyright © 2008-2012 Intel Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 * 23 * Authors: 24 * Eric Anholt <eric@anholt.net> 25 * Chris Wilson <chris@chris-wilson.co.uk> 26 * 27 */ 28 29 #include <drm/drmP.h> 30 #include <drm/i915_drm.h> 31 #include "i915_drv.h" 32 33 /* 34 * The BIOS typically reserves some of the system's memory for the exclusive 35 * use of the integrated graphics. This memory is no longer available for 36 * use by the OS and so the user finds that his system has less memory 37 * available than he put in. We refer to this memory as stolen. 38 * 39 * The BIOS will allocate its framebuffer from the stolen memory. Our 40 * goal is try to reuse that object for our own fbcon which must always 41 * be available for panics. Anything else we can reuse the stolen memory 42 * for is a boon. 43 */ 44 45 static unsigned long i915_stolen_to_physical(struct drm_device *dev) 46 { 47 struct drm_i915_private *dev_priv = dev->dev_private; 48 u32 base; 49 50 /* Almost universally we can find the Graphics Base of Stolen Memory 51 * at offset 0x5c in the igfx configuration space. On a few (desktop) 52 * machines this is also mirrored in the bridge device at different 53 * locations, or in the MCHBAR. On gen2, the layout is again slightly 54 * different with the Graphics Segment immediately following Top of 55 * Memory (or Top of Usable DRAM). Note it appears that TOUD is only 56 * reported by 865g, so we just use the top of memory as determined 57 * by the e820 probe. 58 * 59 * XXX However gen2 requires an unavailable symbol. 60 */ 61 base = 0; 62 if (INTEL_INFO(dev)->gen >= 3) { 63 /* Read Graphics Base of Stolen Memory directly */ 64 pci_read_config_dword(dev->pdev, 0x5c, &base); 65 base &= ~((1<<20) - 1); 66 } else { /* GEN2 */ 67 #if 0 68 /* Stolen is immediately above Top of Memory */ 69 base = max_low_pfn_mapped << PAGE_SHIFT; 70 #endif 71 } 72 73 if (base == 0) 74 return 0; 75 76 /* make sure we don't clobber the GTT if it's within stolen memory */ 77 if (INTEL_INFO(dev)->gen <= 4 && !IS_G33(dev) && !IS_G4X(dev)) { 78 struct { 79 u32 start, end; 80 } stolen[2] = { 81 { .start = base, .end = base + dev_priv->gtt.stolen_size, }, 82 { .start = base, .end = base + dev_priv->gtt.stolen_size, }, 83 }; 84 u64 gtt_start, gtt_end; 85 86 gtt_start = I915_READ(PGTBL_CTL); 87 if (IS_GEN4(dev)) 88 gtt_start = (gtt_start & PGTBL_ADDRESS_LO_MASK) | 89 (gtt_start & PGTBL_ADDRESS_HI_MASK) << 28; 90 else 91 gtt_start &= PGTBL_ADDRESS_LO_MASK; 92 gtt_end = gtt_start + gtt_total_entries(dev_priv->gtt) * 4; 93 94 if (gtt_start >= stolen[0].start && gtt_start < stolen[0].end) 95 stolen[0].end = gtt_start; 96 if (gtt_end > stolen[1].start && gtt_end <= stolen[1].end) 97 stolen[1].start = gtt_end; 98 99 /* pick the larger of the two chunks */ 100 if (stolen[0].end - stolen[0].start > 101 stolen[1].end - stolen[1].start) { 102 base = stolen[0].start; 103 dev_priv->gtt.stolen_size = stolen[0].end - stolen[0].start; 104 } else { 105 base = stolen[1].start; 106 dev_priv->gtt.stolen_size = stolen[1].end - stolen[1].start; 107 } 108 109 if (stolen[0].start != stolen[1].start || 110 stolen[0].end != stolen[1].end) { 111 DRM_DEBUG_KMS("GTT within stolen memory at 0x%llx-0x%llx\n", 112 (unsigned long long) gtt_start, 113 (unsigned long long) gtt_end - 1); 114 DRM_DEBUG_KMS("Stolen memory adjusted to 0x%x-0x%x\n", 115 base, base + (u32) dev_priv->gtt.stolen_size - 1); 116 } 117 } 118 119 120 /* Verify that nothing else uses this physical address. Stolen 121 * memory should be reserved by the BIOS and hidden from the 122 * kernel. So if the region is already marked as busy, something 123 * is seriously wrong. 124 */ 125 #if 0 126 r = devm_request_mem_region(dev->dev, base, dev_priv->gtt.stolen_size, 127 "Graphics Stolen Memory"); 128 if (r == NULL) { 129 /* 130 * One more attempt but this time requesting region from 131 * base + 1, as we have seen that this resolves the region 132 * conflict with the PCI Bus. 133 * This is a BIOS w/a: Some BIOS wrap stolen in the root 134 * PCI bus, but have an off-by-one error. Hence retry the 135 * reservation starting from 1 instead of 0. 136 */ 137 r = devm_request_mem_region(dev->dev, base + 1, 138 dev_priv->gtt.stolen_size - 1, 139 "Graphics Stolen Memory"); 140 /* 141 * GEN3 firmware likes to smash pci bridges into the stolen 142 * range. Apparently this works. 143 */ 144 if (r == NULL && !IS_GEN3(dev)) { 145 DRM_ERROR("conflict detected with stolen region: [0x%08x - 0x%08x]\n", 146 base, base + (uint32_t)dev_priv->gtt.stolen_size); 147 base = 0; 148 } 149 } 150 #endif 151 152 return base; 153 } 154 155 static int find_compression_threshold(struct drm_device *dev, 156 struct drm_mm_node *node, 157 int size, 158 int fb_cpp) 159 { 160 struct drm_i915_private *dev_priv = dev->dev_private; 161 int compression_threshold = 1; 162 int ret; 163 164 /* HACK: This code depends on what we will do in *_enable_fbc. If that 165 * code changes, this code needs to change as well. 166 * 167 * The enable_fbc code will attempt to use one of our 2 compression 168 * thresholds, therefore, in that case, we only have 1 resort. 169 */ 170 171 /* Try to over-allocate to reduce reallocations and fragmentation. */ 172 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 173 size <<= 1, 4096, DRM_MM_SEARCH_DEFAULT); 174 if (ret == 0) 175 return compression_threshold; 176 177 again: 178 /* HW's ability to limit the CFB is 1:4 */ 179 if (compression_threshold > 4 || 180 (fb_cpp == 2 && compression_threshold == 2)) 181 return 0; 182 183 ret = drm_mm_insert_node(&dev_priv->mm.stolen, node, 184 size >>= 1, 4096, 185 DRM_MM_SEARCH_DEFAULT); 186 if (ret && INTEL_INFO(dev)->gen <= 4) { 187 return 0; 188 } else if (ret) { 189 compression_threshold <<= 1; 190 goto again; 191 } else { 192 return compression_threshold; 193 } 194 } 195 196 static int i915_setup_compression(struct drm_device *dev, int size, int fb_cpp) 197 { 198 struct drm_i915_private *dev_priv = dev->dev_private; 199 struct drm_mm_node *compressed_llb; 200 int ret; 201 202 ret = find_compression_threshold(dev, &dev_priv->fbc.compressed_fb, 203 size, fb_cpp); 204 if (!ret) 205 goto err_llb; 206 else if (ret > 1) { 207 DRM_INFO("Reducing the compressed framebuffer size. This may lead to less power savings than a non-reduced-size. Try to increase stolen memory size if available in BIOS.\n"); 208 209 } 210 211 dev_priv->fbc.threshold = ret; 212 213 if (HAS_PCH_SPLIT(dev)) 214 I915_WRITE(ILK_DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 215 else if (IS_GM45(dev)) { 216 I915_WRITE(DPFC_CB_BASE, dev_priv->fbc.compressed_fb.start); 217 } else { 218 compressed_llb = kzalloc(sizeof(*compressed_llb), GFP_KERNEL); 219 if (!compressed_llb) 220 goto err_fb; 221 222 ret = drm_mm_insert_node(&dev_priv->mm.stolen, compressed_llb, 223 4096, 4096, DRM_MM_SEARCH_DEFAULT); 224 if (ret) 225 goto err_fb; 226 227 dev_priv->fbc.compressed_llb = compressed_llb; 228 229 I915_WRITE(FBC_CFB_BASE, 230 dev_priv->mm.stolen_base + dev_priv->fbc.compressed_fb.start); 231 I915_WRITE(FBC_LL_BASE, 232 dev_priv->mm.stolen_base + compressed_llb->start); 233 } 234 235 dev_priv->fbc.size = size / dev_priv->fbc.threshold; 236 237 DRM_DEBUG_KMS("reserved %d bytes of contiguous stolen space for FBC\n", 238 size); 239 240 return 0; 241 242 err_fb: 243 kfree(compressed_llb); 244 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 245 err_llb: 246 pr_info_once("drm: not enough stolen space for compressed buffer (need %d more bytes), disabling. Hint: you may be able to increase stolen memory size in the BIOS to avoid this.\n", size); 247 return -ENOSPC; 248 } 249 250 int i915_gem_stolen_setup_compression(struct drm_device *dev, int size, int fb_cpp) 251 { 252 struct drm_i915_private *dev_priv = dev->dev_private; 253 254 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 255 return -ENODEV; 256 257 if (size < dev_priv->fbc.size) 258 return 0; 259 260 /* Release any current block */ 261 i915_gem_stolen_cleanup_compression(dev); 262 263 return i915_setup_compression(dev, size, fb_cpp); 264 } 265 266 void i915_gem_stolen_cleanup_compression(struct drm_device *dev) 267 { 268 struct drm_i915_private *dev_priv = dev->dev_private; 269 270 if (dev_priv->fbc.size == 0) 271 return; 272 273 drm_mm_remove_node(&dev_priv->fbc.compressed_fb); 274 275 if (dev_priv->fbc.compressed_llb) { 276 drm_mm_remove_node(dev_priv->fbc.compressed_llb); 277 kfree(dev_priv->fbc.compressed_llb); 278 } 279 280 dev_priv->fbc.size = 0; 281 } 282 283 void i915_gem_cleanup_stolen(struct drm_device *dev) 284 { 285 struct drm_i915_private *dev_priv = dev->dev_private; 286 287 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 288 return; 289 290 i915_gem_stolen_cleanup_compression(dev); 291 drm_mm_takedown(&dev_priv->mm.stolen); 292 } 293 294 int i915_gem_init_stolen(struct drm_device *dev) 295 { 296 struct drm_i915_private *dev_priv = dev->dev_private; 297 u32 tmp; 298 int bios_reserved = 0; 299 300 #ifdef CONFIG_INTEL_IOMMU 301 if (intel_iommu_gfx_mapped && INTEL_INFO(dev)->gen < 8) { 302 DRM_INFO("DMAR active, disabling use of stolen memory\n"); 303 return 0; 304 } 305 #endif 306 307 if (dev_priv->gtt.stolen_size == 0) 308 return 0; 309 310 dev_priv->mm.stolen_base = i915_stolen_to_physical(dev); 311 if (dev_priv->mm.stolen_base == 0) 312 return 0; 313 314 DRM_DEBUG_KMS("found %zd bytes of stolen memory at %08lx\n", 315 dev_priv->gtt.stolen_size, dev_priv->mm.stolen_base); 316 317 if (INTEL_INFO(dev)->gen >= 8) { 318 tmp = I915_READ(GEN7_BIOS_RESERVED); 319 tmp >>= GEN8_BIOS_RESERVED_SHIFT; 320 tmp &= GEN8_BIOS_RESERVED_MASK; 321 bios_reserved = (1024*1024) << tmp; 322 } else if (IS_GEN7(dev)) { 323 tmp = I915_READ(GEN7_BIOS_RESERVED); 324 bios_reserved = tmp & GEN7_BIOS_RESERVED_256K ? 325 256*1024 : 1024*1024; 326 } 327 328 if (WARN_ON(bios_reserved > dev_priv->gtt.stolen_size)) 329 return 0; 330 331 /* Basic memrange allocator for stolen space */ 332 drm_mm_init(&dev_priv->mm.stolen, 0, dev_priv->gtt.stolen_size - 333 bios_reserved); 334 335 return 0; 336 } 337 338 #if 0 339 static struct sg_table * 340 i915_pages_create_for_stolen(struct drm_device *dev, 341 u32 offset, u32 size) 342 { 343 struct drm_i915_private *dev_priv = dev->dev_private; 344 struct sg_table *st; 345 struct scatterlist *sg; 346 347 DRM_DEBUG_DRIVER("offset=0x%x, size=%d\n", offset, size); 348 BUG_ON(offset > dev_priv->gtt.stolen_size - size); 349 350 /* We hide that we have no struct page backing our stolen object 351 * by wrapping the contiguous physical allocation with a fake 352 * dma mapping in a single scatterlist. 353 */ 354 355 st = kmalloc(sizeof(*st), GFP_KERNEL); 356 if (st == NULL) 357 return NULL; 358 359 if (sg_alloc_table(st, 1, GFP_KERNEL)) { 360 kfree(st); 361 return NULL; 362 } 363 364 sg = st->sgl; 365 sg->offset = 0; 366 sg->length = size; 367 368 sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset; 369 sg_dma_len(sg) = size; 370 371 return st; 372 } 373 #endif 374 375 static int i915_gem_object_get_pages_stolen(struct drm_i915_gem_object *obj) 376 { 377 BUG(); 378 return -EINVAL; 379 } 380 381 static void i915_gem_object_put_pages_stolen(struct drm_i915_gem_object *obj) 382 { 383 #if 0 384 /* Should only be called during free */ 385 sg_free_table(obj->pages); 386 kfree(obj->pages); 387 #else 388 BUG(); 389 #endif 390 } 391 392 393 static void 394 i915_gem_object_release_stolen(struct drm_i915_gem_object *obj) 395 { 396 if (obj->stolen) { 397 drm_mm_remove_node(obj->stolen); 398 kfree(obj->stolen); 399 obj->stolen = NULL; 400 } 401 } 402 static const struct drm_i915_gem_object_ops i915_gem_object_stolen_ops = { 403 .get_pages = i915_gem_object_get_pages_stolen, 404 .put_pages = i915_gem_object_put_pages_stolen, 405 .release = i915_gem_object_release_stolen, 406 }; 407 408 static struct drm_i915_gem_object * 409 _i915_gem_object_create_stolen(struct drm_device *dev, 410 struct drm_mm_node *stolen) 411 { 412 struct drm_i915_gem_object *obj; 413 414 #if 0 415 obj = i915_gem_object_alloc(dev); 416 #else 417 obj = NULL; 418 #endif 419 if (obj == NULL) 420 return NULL; 421 422 drm_gem_private_object_init(dev, &obj->base, stolen->size); 423 i915_gem_object_init(obj, &i915_gem_object_stolen_ops); 424 425 #if 0 426 obj->pages = i915_pages_create_for_stolen(dev, 427 stolen->start, stolen->size); 428 #else 429 obj->pages = NULL; 430 #endif 431 if (obj->pages == NULL) 432 goto cleanup; 433 434 obj->has_dma_mapping = true; 435 i915_gem_object_pin_pages(obj); 436 obj->stolen = stolen; 437 438 obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT; 439 obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE; 440 441 return obj; 442 443 cleanup: 444 i915_gem_object_free(obj); 445 return NULL; 446 } 447 448 struct drm_i915_gem_object * 449 i915_gem_object_create_stolen(struct drm_device *dev, u32 size) 450 { 451 struct drm_i915_private *dev_priv = dev->dev_private; 452 struct drm_i915_gem_object *obj; 453 struct drm_mm_node *stolen; 454 int ret; 455 456 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 457 return NULL; 458 459 DRM_DEBUG_KMS("creating stolen object: size=%x\n", size); 460 if (size == 0) 461 return NULL; 462 463 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 464 if (!stolen) 465 return NULL; 466 467 ret = drm_mm_insert_node(&dev_priv->mm.stolen, stolen, size, 468 4096, DRM_MM_SEARCH_DEFAULT); 469 if (ret) { 470 kfree(stolen); 471 return NULL; 472 } 473 474 obj = _i915_gem_object_create_stolen(dev, stolen); 475 if (obj) 476 return obj; 477 478 drm_mm_remove_node(stolen); 479 kfree(stolen); 480 return NULL; 481 } 482 483 struct drm_i915_gem_object * 484 i915_gem_object_create_stolen_for_preallocated(struct drm_device *dev, 485 u32 stolen_offset, 486 u32 gtt_offset, 487 u32 size) 488 { 489 struct drm_i915_private *dev_priv = dev->dev_private; 490 struct i915_address_space *ggtt = &dev_priv->gtt.base; 491 struct drm_i915_gem_object *obj; 492 struct drm_mm_node *stolen; 493 struct i915_vma *vma; 494 int ret; 495 496 if (!drm_mm_initialized(&dev_priv->mm.stolen)) 497 return NULL; 498 499 DRM_DEBUG_KMS("creating preallocated stolen object: stolen_offset=%x, gtt_offset=%x, size=%x\n", 500 stolen_offset, gtt_offset, size); 501 502 /* KISS and expect everything to be page-aligned */ 503 if (WARN_ON(size == 0) || WARN_ON(size & 4095) || 504 WARN_ON(stolen_offset & 4095)) 505 return NULL; 506 507 stolen = kzalloc(sizeof(*stolen), GFP_KERNEL); 508 if (!stolen) 509 return NULL; 510 511 stolen->start = stolen_offset; 512 stolen->size = size; 513 ret = drm_mm_reserve_node(&dev_priv->mm.stolen, stolen); 514 if (ret) { 515 DRM_DEBUG_KMS("failed to allocate stolen space\n"); 516 kfree(stolen); 517 return NULL; 518 } 519 520 obj = _i915_gem_object_create_stolen(dev, stolen); 521 if (obj == NULL) { 522 DRM_DEBUG_KMS("failed to allocate stolen object\n"); 523 drm_mm_remove_node(stolen); 524 kfree(stolen); 525 return NULL; 526 } 527 528 /* Some objects just need physical mem from stolen space */ 529 if (gtt_offset == I915_GTT_OFFSET_NONE) 530 return obj; 531 532 vma = i915_gem_obj_lookup_or_create_vma(obj, ggtt); 533 if (IS_ERR(vma)) { 534 ret = PTR_ERR(vma); 535 goto err_out; 536 } 537 538 /* To simplify the initialisation sequence between KMS and GTT, 539 * we allow construction of the stolen object prior to 540 * setting up the GTT space. The actual reservation will occur 541 * later. 542 */ 543 vma->node.start = gtt_offset; 544 vma->node.size = size; 545 if (drm_mm_initialized(&ggtt->mm)) { 546 ret = drm_mm_reserve_node(&ggtt->mm, &vma->node); 547 if (ret) { 548 DRM_DEBUG_KMS("failed to allocate stolen GTT space\n"); 549 goto err_vma; 550 } 551 } 552 553 vma->bound |= GLOBAL_BIND; 554 555 list_add_tail(&obj->global_list, &dev_priv->mm.bound_list); 556 list_add_tail(&vma->mm_list, &ggtt->inactive_list); 557 i915_gem_object_pin_pages(obj); 558 559 return obj; 560 561 err_vma: 562 i915_gem_vma_destroy(vma); 563 err_out: 564 drm_mm_remove_node(stolen); 565 kfree(stolen); 566 drm_gem_object_unreference(&obj->base); 567 return NULL; 568 } 569